What is Sany Excavator Fault Code P117?

Fault Code P117 on Sany excavators indicates a malfunction in the hydraulic pump solenoid control circuit, specifically related to abnormal voltage or current flow detected by the Engine Control Module (ECM). This code typically signals that the ECM has identified either an open circuit, short circuit, or resistance issue within the wiring harness or solenoid valve that regulates hydraulic pump output pressure.

This fault is critical for Sany excavators because the hydraulic pump solenoid directly controls the variable displacement mechanism that adjusts hydraulic flow based on operational demands. When the ECM cannot properly communicate with or control this solenoid, the machine may enter a reduced power mode to prevent potential damage to hydraulic components or the engine itself. For used excavators, this code often appears due to age-related degradation of electrical connections or internal solenoid failures from prolonged exposure to heat and vibration.

Common Symptoms

• Hydraulic system derate resulting in slow or sluggish boom, arm, and bucket movements
• Illuminated malfunction indicator lamp (MIL) or warning light on the instrument cluster
• Intermittent loss of hydraulic power during operation, especially under heavy loads
• Engine may run normally at idle but exhibit performance issues when hydraulic functions are engaged
• Stored diagnostic trouble code P117 visible when scanned with Sany diagnostic software or compatible OBD reader

Potential Causes

The most frequent technical causes for Code P117 on used Sany excavators include:

• Damaged or corroded wiring harness connections at the hydraulic pump solenoid connector, particularly at harness rub points near the engine mounting brackets
• Failed hydraulic pump proportional solenoid valve due to internal coil breakdown or mechanical sticking
• Short circuit to ground caused by abraded insulation where harnesses contact sharp edges or moving components
• ECM pin terminal corrosion affecting signal integrity between the controller and solenoid
• Low battery voltage or poor grounding connections creating voltage drop issues during solenoid activation
• Previous repairs using incorrect wire gauge or improper connector crimping techniques

How to Troubleshoot and Fix Code P117

Step 1: Visual Inspection Begin by thoroughly inspecting the solenoid wiring harness from the ECM connector to the hydraulic pump. On used excavators, pay special attention to harness routing near heat sources and areas where cables may rub against the engine block or chassis. Look for cracked insulation, burnt wires, or green corrosion on connector pins.

Step 2: Electrical Testing Disconnect the hydraulic pump solenoid connector and use a digital multimeter to measure solenoid coil resistance. Typical specifications for Sany solenoids range between 10-25 ohms (consult your service manual for exact values). Test for continuity to ground on both solenoid terminals—any continuity indicates a short circuit requiring harness or solenoid replacement.

Step 3: Voltage Supply Check With the ignition on and engine off, backprobe the solenoid connector to verify the ECM is providing proper control voltage (typically 12-24V depending on model). If voltage is absent, trace the circuit back to the ECM, checking for blown fuses, broken wires, or corroded ECM pins.

Step 4: Solenoid Function Test If electrical readings are within specification, the solenoid valve itself may have internal mechanical failure. Remove and bench-test the solenoid using a regulated power supply, listening for the audible click and checking for smooth plunger movement. For used machines, internal varnish buildup or worn seals commonly cause intermittent operation.

Step 5: Clear Code and Verify Repair After repairs, clear the fault code using Sany PC-E1 diagnostic software or equivalent tool, then operate the machine under load to confirm the issue is resolved and P117 does not return.

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Disclaimer: This guide provides general troubleshooting information for educational purposes. Always consult the official Sany service manual for your specific excavator model and serial number. If you lack proper diagnostic tools or experience with high-pressure hydraulic systems, seek assistance from a certified Sany technician or qualified heavy equipment mechanic.